Microsoft Office 365 Phishing Attack Uses Multiple CAPTCHAs

Microsoft Office 365 Phishing Attack Uses Multiple CAPTCHAs

Researchers are warning of an ongoing Office 365 credential-phishing attack that's targeting the hospitality industry – and using visual CAPTCHAs to avoid detection and appear legitimate. ... The multiple CAPTCHAs serve as backups, in case the first one gets defeated by automated systems, said researchers.

Researchers are warning of an ongoing Office 365 credential-phishing attack that’s targeting the hospitality industry – and using visual CAPTCHAs to avoid detection and appear legitimate.

CAPTCHAs – commonly utilized by websites like LinkedIn and Google – are a type of challenge–response test used to determine whether or not the user is human, such as clicking on the parts of a grid that have a specific object pictured. Cybercriminals have previously utilized CAPTCHAs as a way to defeat automated crawling systems, ensure that a human is interacting with the page and make the phishing landing page appear legitimate.

Though the use of CAPTCHAS in phishing attacks is nothing groundbreaking, this attack shows that the technique works – so much so that the attackers in this campaign used three different CAPTCHA checks on targets, before finally bringing them to the phishing landing page, which poses as a Microsoft Office 365 log-in page.

“Two important things are happening here,” said researchers with Menlo Security, in a post this week. “The first is that the user is made to think that this is a legitimate site, because their cognitive bias has trained them to believe that checks like these appear only on benign websites. The second thing this strategy does is to defeat automated crawling systems attempting to identify phishing attacks.”

Menlo Security’s Director of Security Research, Vinay Pidathala, told Threatpost said that researchers are unsure of how many users were specifically targeted, however, the industries targeted by this campaign were primarily technology, insurance, and finance and banking.

The multiple CAPTCHAs serve as backups, in case the first one gets defeated by automated systems, said researchers.

In the first CAPTCHA check, targets are simply asked to check a box that says “I’m not a robot.”

After that, they are then taken to a second CAPTCHA that requires them to select for instance all the picture tiles that match bicycles, followed by a third CAPTCHA asking them to identify, say, all the pictures that match a crosswalk. Attackers also do not use the same CAPTCHAs – researchers said, during their testing they came across at least four different images utilized.

Finally, after passing all these checks, the target is taken to the final landing page, which impersonates an Office 365 log-in page, in an attempt to steal the victims’ credentials.

cloud security web security captcha compromised email credential theft domain email credentials hack menlo security microsoft office 365 phishing phishing attack recaptcha scam

Bootstrap 5 Complete Course with Examples

Bootstrap 5 Tutorial - Bootstrap 5 Crash Course for Beginners

Nest.JS Tutorial for Beginners

Hello Vue 3: A First Look at Vue 3 and the Composition API

Building a simple Applications with Vue 3

Deno Crash Course: Explore Deno and Create a full REST API with Deno

How to Build a Real-time Chat App with Deno and WebSockets

Convert HTML to Markdown Online

HTML entity encoder decoder Online

Microsoft Teams Phishing Attack Targets Office 365 Users

Up to 50,000 Office 365 users are being targeted by a phishing campaign that purports to notify them of a “missed chat” from Microsoft Teams. Researchers are warning of a phishing campaign that pretends to be an automated message from Microsoft Teams.

Office 365 Phishing Attack Leverages Real-Time Active Directory Validation

Attackers check the victims' Office 365 credentials in real time as they are typed into the phishing landing page, by using authentication APIs.

OAuth Consent Phishing Ramps Up with Microsoft Office 365 Attacks

Attackers gain read-only permissions to snoop around Office 365 accounts, including emails, contacts and more. An APT known as TA2552 has been spotted using OAuth2 or other token-based authorization methods to access Office 365 accounts, in order to steal users' contacts and mail.

Unsecured Microsoft Bing Server Leaked Search Queries, Location Data

Data exposed included search terms, location coordinates, and device information – but no personal data.

APT28 Mounts Rapid, Large-Scale Theft of Office 365 Logins

The Russia-linked threat group is harvesting credentials for Microsoft's cloud offering, and targeting mainly election-related organizations.